Electric smelting-furnace.



F. T. SNYDER.

ELECTRIC SMELTIVNG FURNACE. APPLICATION FILE!) MAR. I. 1917- Patented Jan. 22,1918.

UNITED STATES PATENT OFFICE.

FREDERICK T. SNYDER, OF OAK PARK, ILLINOIS.

I ELECTRIC SMEL'PING-FUBNACE.

, To all 'wlwm it'may concern:

'' shaft furnacesfor the lower surface of the column of ore, as it fgfiravitates into the melting chamber vof the mace, to be fused, due

tothe intense heat, into a solid crust or arch,

1 which acts as abarrie'r and prevents the ore above it from feedingdown; This causes considerable delay in vthe-melting process.

.Furthermore, this crust-formation or arch,

when brokenby the increased pressure brought to bear thereon, causes the entire column to drop to the bottom of the furnace with great force, resulting in an intermittent feed and giving rise to possible damage to the furnace. y

The present invention aims to overcome the various disadvantages caused by the arching of the ore, which is common in furnaces as now constructed, and has for its primaryobject the provision of means whereby the charge is fed into the furnace "from the sides thereof, in such manner as to pr' v'iit archingvwother object of the present invention resi of an electric smeltmg furnace which shall be provided with a roof, under which the charge is adapted to be fed.

A further ob ect is the pr0vi sio1i of means whereby the charge, prior to its introduc- .tion into the 'melting chamber ofthe furnace; is forced up'wardlv over an inclined surface to thereby.permitthe volatile metals, which rise from the molten sla'g 1nv the form of gases and condense in the char e, as

. I lit is being fed in, to trickledown to said inclined surface through the charge and to be,

" drawn off therefrom.

Other objects and advantages will be apparent from the following description, taken Specification of Letters Patent.

in connection with-the accompanying drawings, wherein the preferred embodiment of the invention is illustrated. a

' Figure 1 is a top, plan view partly in sect-ion of an electric smelting furnace embody in my mprovements.

, i'ga2 is across section taken on 'the line 2-2 of'Fig. 1; and

Fig. 3 is a crosssection taken on the line 3-3 of Fig. 1.

Referrin more in detail to the drawings, the body 0 the furnace is shownat 1 and is provided with the usual refractory lining 2, a heat insnlatin lining 3 and an outer metallic shell 4. T e melting chamber is indicated 'at 5 and. is shown provided with the bottom contact 6, which in the present instance, is preferably a-metal having a low melting point and a high boiling point, the specific gravity of which is greater than the specific gravity of the metal being operated upon,' ih order that the same will remain in the bottom of the chamber 5 at all times. The metal used for this bottom contact 6 is preferably lead. Leading from the chamber 5 to one side of the body of the furnace, is shown a-passage 7, through which the molten metal forming the bottom contact flows into contact with the block 8, preferably composed of graphite. Connected with this block 8, is shown the copper lead 9, which conducts the current to the bottom contact 6, through the block 8, said block being provided to protect the end of the copper lead from-,injurv, which would be caused if the s' 'in the provisinn s nre was brought into direct contact with thenroite ndearlr l-heatap l tglle of the furnace is shown at 10, through which'slag is: y

drawn out through the spoutll. Above the body l, is a suitable frame 12, in which is mounted the roof 13 of the furnace. Projecting through the roof 13 and terminating above the meltingchamberfiis the electrode It, said electrode being preferably clamped between suitable arms '15 projecting outwardly from theupright 16 and overhanging the roof of the furnace. substantially as shown. By means of suitable operating mechanism (not shown), said upright 16 may be raised or lowered to adjust the electrode 14 with relation to the bottom contact Patented Jan. 22, 1918.

I applleatiunfled March 1, 1917. Serial No. 151,719.

out. The frame 12 6, as may be required. The roof 13 shown in the drawings is provided with a plurality of charging ports 17, through which the charge is fed into the furnace as hereinafter pointed preferably extends above the top of the rod 13 as shown, in order that a considerable amount of ore may besupported above the furnace at one time. It will be noted from 'the foregoing that a roof has been provided which may be readily removed from the body of the furnace, to

thereby permit of easy access theretolfor purposes of cleaning or repairing the same.

t may be found j more desirable in practice eater number of charging ports than is s own in the drawings, and accordingly, it is not intended to limit the present invention to any particular number of these ports, the right being reserved to use a greater or less number than shown.

Mounted preferably below each of the charging ports 17 of the roof 13, are "a plurality of feeders 18, shown pivoted at 19, said feeders being adapted to be reciprocated in and out through the openings 20 provided in the side of the furnace, to push the charge into the meltin chamber 5, as it gravitates down throng said charging ports. It will be'noted that many different forms of mechanism maybe devised to operate these feeders, and accordingly no'particular form has been shown in the drawings, the right 'being reserved to use any desired form of mechanism. to accomplish this result. It is preferred to have the feeders 18 all working forward at the same time,

in order that pressure exerted thereby will instance zine, present in the ore, being fed into the furnace, the same will rise in the form of a gas when subjected to the heat produced therein and willcondcnse in-'the charge as it is fed in bythe pushers 18. The top wall of' the body of the furnace is preferably inclined dowmvardly away from the melting chamber 5. as shown at 20. It will be noted from this that the charge, after it has been fed through the charging ports 17, will be forced inwardly and -upwardly over the inc ined surface 20, by the feeders 18. This effectively prevents any arching of the charge as it is fed into the meltin chamber of the furnace for the reason that if a short arch forms, it will be concentric with the are between the electrode and the, charge and will therefore lack the necessary upper abutment to enable it to resist pressure. A plurality of gutters 21 are positioned at the outer lower end of the inclined surface 20. This provides means whereby the metal which has been condensed in the charge, may trickle down thus separating said metal from t tter 21, e charge, as it is being forced by. the feeders 18 into the melting chamber 5. From these gutters 21, the condensed metal is conducted through the same and into the into a. suitable trough 22, from whence it is drawn ofl through the' outlet 23.

In practice, it has been found that certain grades of ore are so fine as to prevent the condensed metal from seeping through the same and flowing down the inclined surface 20 and into'the gutters 21. When such ore is encountered, 1t is preferred to make use of what may be termed column charging. As is' well known, it is common to mix coke with ore as the same is fed into the furnace in order to provide for the necessary reduction According to tlie'present invention however, when extremely fine ore is encountered, it is preferred to feed the ore and coke into the furnace through the charging ports in separate columns. For instance, this may be accomplished by feeding a column of coke and a. column of ore, through each of the charging ports, substantially-as shown in Fig. 3 of the drawings, the column of coke being positioned adjacent the outer wall of the frame 12. It will'thus be seen that as the feeders 18 work inwardly, the coke is forced upwardly over the inclined surface 20 and into themelting chamber 5, thereby iprovidiug means whereby the condensed metal may gravitate therethrough and down said surface 20 into the gutters 21. If preferred, the column char, in,-' may be effected by feeding coke through alternate charging ports and ore through the remaining ones In other words, thecolumn charging may be effected either radially or circumfcrentially.

It is obvious that various changes and modifications may be made 'in the structure shown and describedherein without departing from the spirit of the invention, and the right is therefore reserved to make such changes and modifications as fall within the scope of the appended claims.

llaving'thus described my invention, what I claim as new and desire to secure by Lette rs Patent of the United States is:

1. The method of charging an electric furnace whichconsists in feedingthe charge radially inward toward the are from all sides, in a horizontal plane only.

2. The method ofcharging an electric'fura; charge into said furnace laterally under .fsaid roof toward said'electrode'hereby a rec are may be maintained between said electrode and said charge and the escape of volatile constituents of the charge prevented by said roof.

4. An electric furnace comprising a body a roof, an electrode projecting through said roof whereby an arc may be maintained between said electrode and bottom of the furnace, and means for feeding the charge toward said are from all si es whereby said charge is melted down before'reaching said electrode, thereby maintaininga free are in the center of a crater.

5. An electric furnace comprising a base, lateral feeding means associated therewith,

a frame removably supported on said base near the periphery. t

and a roof carried by said frame, whereby said roof may be removed to expose said feeding means and the meltingchamber.

6. An electric furnace comprising a body provided with a melting chamber, a roof provided with a plurality of charging ports hereof, and means adapted to force the charge radially inward toward said melting chamber, said charge being in contact with said roof adjacent said ports to seal said melting chamber.

7. An electric furnace of the arc ty e, comprising a body, a meltin cham r therein, the upper wall of said c amber being inclined downwardly away from the interior of said chamber, and means adapted to force a charge of ore into said chamber over said inclined wall 'to permit of the separation of condensed metal therefrom.

8. An electric furnace of the arc type, comprising a body, a melting chamber therein, the upper wall-of said chamber being 'inclined downwardly away from the incharge a body portion,

' furnace,

tcrior of said chamber and means adapted to force a' charge into said chamber over said inclined wall to permit of the separation of condensed metal therefrom, an means t5 receive the metal thus separated. 9. An electric furnace comprising a body portion, a melting chamber positioned therebeing provided with an upperwall inclined downwardly away from the interior of said chamber.

10. An electric furnace comprising a roof,

a body portion, and reciprocating means intherebetween adapted to force a laterally into said chamber. An electric furnace comprising a roof, and means interposed there between adapted to force a charge laterally into said chamber and into contact with the under side of said roof, to, seal said chamber.

12. The method of charging an electric which consists in feeding a column terpose oforecnd a column oficombustible material downwardly near the outer circumference thereof and then forcing said charge laterally into the melting chamber in contact with said roof.

13. The method of charging an electric furnace which consists in feeding radially the charge in the' positioned and jeans disposed columns of ore and combustible material downwardly into said furnace, said combustible material being outside of said ore and then forcing such charge laterally into 'the melting chamber.

14. The method of charging an electric furnace which consists in feeding radially disposed columns of ore and combustible material downwardly into said furnace and thenforcing the same laterally in layers into the melting chamber.

15. The method of charging an electric furnace which consists in feeding radially disposed columns of ore and combustible materialdownwardly into said furnace and then forcin the same laterally in layers over an inc lined surface into the melting chamber.

16. The method of chargin an electric furnace which consists in feeding radially disposed columns of ore and combustible material downwardly into said furnace and then forcing the same laterally -in layers into the melting chamber, the layer of combustible material being disposed beneath the layer of ore.

17. The method of charging an electric furnacewhich consists in feeding radially disposed columns of ore and combustible material downwardly into said furnace and then forcing the same "laterally in layers over an inclined surface into the meltin chamber, the layer of combustible materia being disposed beneath the layer of ore and in contact with the inclined surface.

18. An electric furnace comprising a body portion, a frame mounted thereabove, a'roof within said frame and an electrode projecting through said roof.

19. An electric furnace comprising a body portion, a frame mounted thereabove, a roof positioned within said frame and an electrode projecting through said roof, said roof and said frame being removable from said body portion.

20. An electric furnace provided with a refractory roof, a roof band supporting the same, means for feeding a charge laterally under said roof toward a melting chamber, for supporting said roof band, whereby said roof may. be removed 'to expose said chamber and. said feeding means for inspection.

21. An electric furnace comprising a body portion, a frame, and a roof mounted within said frame and above said body portion, said frame extending above said roof and adapted to coiipgrate therewith to support the material to be fed into said furnace.

22. An electric furnace comprising a body portion, a roof mounted thereon, and a frame surrounding said roof and adapted to cooperate therewith to support the mamit of said material bcing fed downwardly port is sealed a in columns around the outer circumference therethrough. of said roof into said furnace. In witness whereof, I hereunto subscribe 10 23. An electric furnace having a roof pr0 my mine this 26th day of February A. D 5 vided with a chargin port and a feeder ar- 1917.

ranged to force theeiarge laterally against the inner edge of said port, whereby said FREDERICK T. SNYDER.-

gainst the escape of gas 

